Apparatus for fluidizing and pressurizing fire-extinguishing dry chemicals



Sept. 8, 1953 ALLEN APPARATUS FOR FLUIDIZING AND PRESSURIZING FIRE-EXTINGUISHING DRY CHEMICALS Filed Jan. 31, 1951 N mm ATTORNEY Patented Sept. 8, 1953 SURIZIN G CHEMICALS FIRE EXTINGUISIHNG DRY Alden Allen, Menominee, Mich., assignor to Ansul Chemical Company, Marinette, Wis., a corporation of Wisconsin Application January 31, 1951, Serial No. 208,822 3 Claims. (Cl. 169-11) This invention relates to an apparatus and method for fluidizing powdered fire-extinguishe ing chemical and for pressurizing containers in which the dry chemical is stored for supplying a stream of fluidized dry chemical for fire-extinguishing purposes. a An essential requirement in dry chemical fireextinguishing apparatus is'that the storage container having the dry chemical should be instantly and completely fluidized or aerated as soon as gas pressure is introduced therein so that a fluidized stream of dry chemical under predetermined pressure is instantly ejected from the storage container when needed to extinguish a fire. In prior constructions, difllculty has been experienced in producing streams of fluidized dry chemical having a predetermined ratio of dry chemical to gas for substantially the entire time the dry chemical stream issues from the storage container. In order'to attain this objective, it is necessary to build up the pressure at the top and bottom zones of the container at substantially the same rate so that the gas introduced into the container will fluidize substantially all the dry chemical in the container and pressurize all portions of the container at substantially the same rate.

According to the present invention a fire-extinguishing apparatus is provided comprising a storage container for powdered dry chemical having means to supply gas under pressure thereto and for subdividing the gas stream within the container into opposed subdivided streams adjaoent the bottom of the container and directing the subdivided streams towards the lateral walls of the container. A plurality of outlets is also provided for the fluidized dry chemical which are adapted to be connected to hose lines for conducting streams of fluidized dry chemical to the location where a fire is to be extinguished. Further advantages and objects of the invention will be apparent from the following specification and drawings, wherein Figure 1 is a vertical partial sectional View of a storage container for powdered fire-extinguishing dry chemical, and

Figure 2 is a sectional view taken on lines 2-2 of Figure 1.

Referring to the drawings, the fire-extinguishing apparatus comprises a metal storage container l0, preferably cylindrical in form, for storing powdered dry chemical therein, such as disclosed in Patent 1,793,420, February 17, 1931. The container has a smooth concave bottom surface merging with the vertical walls thereof. The

container is supported on a base 9- and is provided at the top with a removable closure cap,v II for introducing fresh dry chemical into the cone tainer. .-A gas inlet I 2 is provided at the top of the container which is adapted to be suitably con! nected to a source of gas pressure, such as cylinders of compressed carbon dioxide, nitrogen, or air which may be under a pressure of about 2000 lbs. per square inch. The inlet I2 is cone nected to a tube I6 extending within the container and preferably terminating adjacent-the bottom of the container in a fitting H to which opposed nozzles and 26 are connected. The inlet l2 may also be advantageously positioned in any suitable location in the lower portion of the container Hi. When gas under pressure-is introduced into inlet tube [6 the gas stream will besubdivided; at the fitting ll toproduce two opposed gas streams whichwill be directed toward the lateral walls of the container as indicated by the arrows shown in Figure 1. The gas nozzles 25 and 26 preferably terminate at a point spaced from the vertical axis a distance of about onehalfthe radius ofthe container 10 so as to be spaced away a suflicient distance from the flared outlet l9jto prevent undue loss of pressurizing gas by entering-outlet l9 before passing into the body of the container for fluidizing the dry chemical therein. This construction thus avoids diluting the expellant stream of dry chemical beyond a predetermined. maximum value so as not to substantiallyalter the desired ratio of ,d ry chemical to'gas in the expellant stream. An inwardly flared outlet I 9 is provided adjacent the bottom of the container for entry therein of fluidized dry chemical. The outlet I9 is connected by a short pipe 8 to a fitting 20 to which pipes 2| and 22 are connected. Pipes 2| and 22 are connected to outlet ports 23 and 24, respectively, provided in the walls of the container 10. These ports are suitably connected to hose lines for conducting fluidized dry chemical to the site where a fire is to be extinguished.

In operation, container l0, being substantially filled with powdered dry chemical, is suitably connected at its inlet I 2 to a supply of compressed gas, such as nitrogen for example, at about 2000 lbs. per square inch pressure. The gas will be conducted down the tube ii to the bottom of the container and the stream will be subdivided by fitting I1 into two streams which will be emitted in opposite directions through nozzles 25 and 26 in a substantially radial direction against the'lateral walls of the container.

The emitted gas will force a path through the dry chemical to the top of the container fluidizing the dry chemical and at the same time pressurizing the upper and lower regions of the container at about the same rate until an internal pressure of about 200 to about 250 lbs. per square inch is established. As additional gas is admitted to the container,

outlet l9 and travel upwardly in a path substantially parallel to the vertical axis of the container until it reaches the fitting 20 where it will be subdivided into two streams and pass through pipes 2| and 22 in a path substantially radially of the container and out through outlet ports 23 and 24. The shape of outlet I9 is flared inwardly in order to facilitate flow of the fluidized dry chemical and at the same time it tends to increase the velocity of the dry chemical stream passing through the more constricted passage thereof whereby the dry chemical stream issuing from the container will be in the desired fluidized condition and have a predetermined ratio of dry chemical and propellant gas.

In utilizing the present apparatus it is possible to fiuidize substantially all the dry chemical in the container and pressurize the container throughout at substantially the same rate throughout and to admit further expellin gas in the container to maintain the pressure within the container to expel the fluidized dry chemical without increasing or altering the ratio of dry chemical to gas in the expellant stream.

Changes and modifications may be made of the details of the invention herein described which are intended to be included within the scope of the appended claims.

' I claim:

V 1. A container for storing powdered fire-extinguishing dry streams of fluidized dry chemical comprising a gas inlet tube extending longitudinally within said container for supplying gas under pressure, a fittingconnected to the lower end of said tube, nozzles connected to said fitting, said nozzles terminating at a point spaced from the vertical axis of said container at a distance of about one-half the radius of the container and being positioned to direct streams of gas substantially radially within said container into impingement against the walls of the container for fluidizing the dry chemical stored in said container and pressurizing the upper and lower zones of said container, an outlet positioned within the said container the fluidized dry chemical will be forced to enter the inwardly flared chemical therein and providing adjacent the bottom thereof for permitting fluidized dry chemical to pass therethrough, said outlet being connected to conduits communicating with outlet ports for conveying streams of fluidized dry chemical from said container.

2. A container for storing powdered fire-extinguishing dry chemical therein and providing streams of fluidized dry chemical comprising a gas inlet tube extending longitudinally within said container for supplying gas under pressure, the lower end oi said tube terminating adjacent the bottom of said container, a fitting connected to the lower end of said tube, nozzles connected to said fitting, said nozzles terminating at a point spaced from the vertical axis of said container at a distance of about one-half the radius of the container and being positioned to direct streams of gas substantially radially within said container into impingement against the walls of the container for fluidizing the dry chemical stored in said container and pressurizing the upper and lower zones of said container at substantially the same rate, an outlet positioned within the said container adjacent the bottom thereof for permitting fluidized dry chemical to pass therethrough, said outlet being connected to conduits communicating with outlet ports for conveying streams of fluidized dry chemical from said container.

3. A container for storing powdered fire-extinguishing dry chemical therein and providing streams of fluidized dry chemical comprising an inlet tube extending longitudinally within said container :ior supplying gas under pressure, said tube terminating adjacent the bottom of said container, nozzles terminating at a point spaced from the vertical axis of said container at a distance of about one-half the radius of the container and connected to said tube adjacent the bottom of said container for emitting gas streams radially of said container to impinge against the inner walls of said container for iiuidizing the dry chemical stored in said container and pres-.- surizing the upper and lower zones of said container at substantially the same rate.

ALDEN ALLEN. 1."

' References Cited in the file of this patent v UNITED srs'rzs PATENTS Jan. 1,1952 

